High speed missile



s. a KNAUSENBERGER 3,008,413

Nov. 14, 1961 HIGH SPEED MISSILE Filed May 24, 1956 2 Sheets-Sheet 1 R w N @E R .52: EH 2 E8 6 I525 ENE m 0 0 Ndmw U w/f mdm M 1 @2596 Swfimu K E m m 6 n 0;

QZEmDQ PIE 5 m ATTORNEYS Nov. 14, 1961 G. E. KNAUSENBERGER 3,008,413

HIGH SPEED MISSILE Filed May 24, 1956 2 Sheets$heet 2 FIG.6

FIG. 5

6150M E. KNAUSE/VBERGER INVENTOR.

ATTORNEYS United States atent 3,008,413 Patented Nov. 14,1961

Free

My invention relates to reaction-propelled missiles and particularly to reaction-propelled underwater missiles.

The use of reaction type propulsion means for propelling missiles is now quite well known and has been developed to a more or less great degree. However, the form of underwater missiles having such propulsion means are of the conventional form, i.e., they have an ogive or a more or less pointed front portion, an elongated center portion, and a tapered rear portion, said rear portion, containing the steering and propulsion means. It is also well known that when an underwater missile having the conventional shape as described above is driven at the high speeds attainable by use of reaction type propelling means, such bodies become unstable and develop undesirable characteristics. This is due in large part to the phenomenon known as cavitation. Since an elongated body moving through a medium such as water is inherently unstable, fins are provided on the rear portion of the body to provide stability and allow control of the body. In such an elongated body without fins, the center of pressure is forward of its center of gravity. The center of pressure on such a body is a point on the body where a single force will produce the same effect as the integrated product of the pressures on the body times the area of the body subjected to said pressures. It is this condition which makes such a body inherently unstable. However, attachment of fins to the rear of the body moves the center of pressure behind the center of gravity and when the body tends to pivot about its center of gravity, the resultant force at the new center of pressure produces a restoring moment to the body. The magnitude of this moment is defined by the magnitude of the forces involved and the distance between the center of pressure and the center of gravity. For this reason, it is desirable to have the center of gravity as far forward as possible and the center of pressure as far rearward as possible. Also, when such a body travels at a very high speed through a medium such as water, cavitation will take place at the front and fin parts and negative dynamic pressures exist at the fin or rear parts, thus upsetting the pressure distribution and stability condition.

This arrangement has proved entirely satisfactory at the present day relatively low speeds of propeller-driven missiles. However, as mentioned previously, this arrangement developes an undesirable characteristics at high speeds and is highly objectionable at extremely high speeds.

In accordance with the present invention, there is provided an under-water missile having a cusp-shape through substantially its entire forward portion. In the preferred embodiment, a low-thrust slow -burnin g reaction-type venting motor or equivalent gas producing means is mounted in the rear portion of the forward portion of the missile and a high-thrust quick-burning reaction-type propulsion motor is mounted rearwardly of the venting motor whereby the gases of the venting motor pass between and completely fill the space between the outer surface of the propulsion motor and the wall of the bubble formed by the passage of the missile through the water, thus maintaining the pressure in the bubble at a value at least as high as static pressure during the majority of the travel of the missile. the propulsion motor is preferably such that during regu- The length and diameter of speeds not heretofore attainable.

lar travel a slight deviation of the missile will cause the periphery of said motor to strike the bubble wall and during non-vented travelonly a smallrear portion will be in contact with the bubble wall.

One object of my invention is to provide a missile which is stable and controllable at substantially all speeds, especially the higher speeds.

Another object of my invention is to provide a missile having a degree of stability at high and extremely high Another object of my invention is to provide a missile that does not require stabilizing fins.

Still another object of my invention is to provide a .body that cooperates in a new and unique fashion with .speed underwater missile having a minimum of cavitation and a maximum of stability notheretofore attainable.

Still another object of my invention is to provide an underwater missile having the propulsion motor means mounted such as to aid inmaintaining the stability of the missile. I

Another object of my invention is to provide an underwater missile wherein the center of pressure is maintained rearwardly of the center of gravity without the use of stabilizing means.

Still another object of my invention is to provide an underwater missile that is substantially not subject to negative dynamic pressures.

Another object of my invention is to provide a highspeed missile that is peculiarly adapted for travel in a dense medium or for travel at supersonic speeds through a compressible medium of variable density.

These and other objects and advantages of my invention will be better understood by reference to the accompanying description and drawing wherein like numerals refer to like parts and in which:

FIGURE 1 shows a graph of the pressure distribution in any one plane over one-half of abody with a slight amount of cusping approaching the profile of a cone;

FIGURE 2 shows a graph of the pressure distribution in any one plane over one-half of a body with increased cusping;

FIGURE 3 is a longitudinal view, partly in section, of my missile in its simplest form;

FIGURE 4 is a longitudinal view, partially in section, of a preferred embodiment of my missile according to the present invention;

FIGURE 5 is a fragmentary longitudinal view showing the preferred relation of the rear portion of the missil and the bubble wall during regular travel; and

FIGURE 6 is a fragmentary longitudinal view showing the preferred relation of the rear portion of the missile and the bubble wall during non-vented travel.

FIGURE 1 shows a graph of the pressure distribution in any one plane over one-half of a body with a small amount of cusping and approachirrg'the profile of a cone. The ordinates represent the length of the body, the rear being at the extreme left and the front at the extreme right, and the abscissa represents dynamic pressure in pounds per square foot, shown on the graph as the pressure coefficient. FIGURE/2. shows a graph of the pressure distribution in any one plane over one-half of a body with increased cusping. The ordinates and abscissa for FIG- 'URE 2 are identical with those of FIGURE 1. The

dynamic pressure for both. cases may be found by the formula:

per second.

Zeroyor is static orreference pressure, i.e., the pressure on the body determined by the depth of-thebody in the water. It will be noted that in FIGURE 1 and FIGURE 2., thepressure line does not extend to the right han'd' limit of the graph. This is due to'the fact that the :pressure on the nose is-dependent on: the bluntness of the V v nose-aud tor amore-bl-unt: nose, the line-wi1l-rise higher, 7

and vice versa. With reference to FIGURE 1,:it should befinoted that 'for a bo'dy havinga slightdegree of cusping and approaching the profile of a come, the pressure decreases in a rearwardly direction until just forwardof the rear edgewhere it'drops'ofirapidly to-zero or static pressure. -Hwever, as shown in FIGURE 2, it :willbe noted that with increased -cuspingthepressure on the .riose .iSCCfiOI). .is decreased r and that it increases asone moves rearwardly andireaches a .valuegreater than-that .shown in FIGURE 1. This. efiect:isjuStTtheEreverSe of 'thatrfor arcone-and. is.:due -to the decreased cone angle at the nose and the increased angle of'the. surface: of. the rear portion of thelbodyto the medium with; respect to the longitudinal'axis ofithe body. This effect is the basis for allowing-adjustment of the location .of; the center ofpressure, the determination of which will be more fully: explained hereinafter. With: reference toIFIGURE 2, it will-also be'noticedthat as 'the'rearedge is nap-- preached, the pressure drops off to a negative pressure 'withzrespect to thereference or :static'pressure. This t phenomenon .is .dueto' the :cavity or. bubble that is. formed behind such body as 'llZTIIlOVCS through the 'medium. When the effect of the bubble has'been properly-compensated for, as ismore' fully explained later. herein, the

"pressure curve at the rear will take'lthe; form "ofthe broken line with the indicated increases in-pressure, :andnegative -.dynamic'pressures-will"be eliminated :as'is not possible :onpresent day-torpedoes.

The station of center'ofpressure of my: body equivalent to that previously described; for conventional bodies, may -:b.e located by integrating the area enclosed by the; pressure tgraph. ;It mayalso be located-byusinggthe formula:

:where-fSt ?:isz.the distanceiifrormthe rearof the missile :asv shown in FIGURE 3, in a forwardlydireetion at the endaof which-is located thestation of the'centerof presr:sure,' -fL'is; the length .of' the body asshown in. FIGURE .3, .fd: is:the largest'or. rear diameter of said-body, and

h is the greatest perpendicular distancebetween :a-rpoint .onzthesurface of saidbody and a straightlinedrawn from the periphery of the rear edgesofzsaid:body.:and the I "periphery of the point'orfront portion of :said' body. If

1 it is .desired to -:only approximately-locate :the station 2 of center of pressure, the formula:

S t ,'/L='% (1-8/3 Xh/ i) 7 maybe 'used'where ".S, t ',.l;, i and 'd. are. the. same as defined above. 7 For convenience, thestation-ofcenter of pressure is written as:.St '/.L sothatit is 'defined as afra'ction 'ofthe total length oftheibo'dy as shown in .FIGURETI f a TI-t'is tobe noted thatithe, particular operating ,parameiters of a missile incorporatingthe present inventionmay vary withinwide limits andvvillsubstan'tially determine the various critical dimensions vo f theibjody as.' indicated above; hence. it is impossible to. specify such .withany aegree of' accuracy. Further, the utilization 'and. proce- "dureforithe application of .operat-ing parameters'.to the fdesign' of a missile. after-the, principles or design .andithe .4 necting the front 10 and the periphery 13 which increases in steep=ness--concavely"as-it"approaches the rear"surface 11 whereby a cusp shaped body of revolution is formed. A forward compartment comprises the majority of: the length of the body and is adapted to carry the load or explosive charge whichipreferably. should also constitute the majority of the weight of the .body. so that'thei center of, gravity of the body liesas: far forward as possible in order to secure-themaximum distancetbetweemthe. .center of gravity and its-station of'the center of pressure. An area 15 islocate'dQinlthe rear'portion of the body along the -longitudina-l axis and adapted to receive, a propulsion 'motorof 'the'reaotion type and its associated parts. 'Said motor may be either a conventional=solid fuel type or a liquidoragas 'fueltype. Obviously'the diameter and length of area-15 will be dependent on] the size and type of'reaction motor that is used and 'whe'ther cooling for-themoto'ri-is considered necessary' or'not. "A V 'l-iqu-id='fuel type motor is iridicated'schematically with' a'y section broken away wherethe'numeral 16 indicates-a combustion chamber-and the numeral 17 indicates-an exhaust noz zle through vvhich thev combustion gases-are exhausted in 'the conventional-manner to provide the propulsion of the missile. Theinjection means, the ignition means, and the like are notshown, since they maybe of any conventional type r and are not essential to the invention. Area 15 is surrou'de'd by an annular =area 19 and preferably contains the ;instrumentation for the 'missilesuch as,f-for examplew depth controls, test instrunrentsgdetectionflgear, control means, and the like. 'The dimensions of area 19 are dependent on the 'size. and type ofrpropulsion motor used and the type of instrumentation and controls, if any, that:rit is desired to carry .in' the: missile. No'li-mitation with r'espect to the content of' area 19 .is intended :other:' than that it is preferable that such notcause. thecenterof'gravity of the body to -lierearwardly of. the center. ofpressure of the body. spacef18 is: located between the forward: portion 14 and the Y motor are'alS for the storage :of fuel and'asshownin' FIGURE 3, space 18 is adapted for :the storage ofaa liquid. or gaseousfuel. 'However, assmentionedpreviously herein, sa solidfuel type motor may" betused if desiredandwhere suchis the case, :space :18 may be omitted as the circumstances may require. Further, if my missileis'to beof fthezsimplestraight rurmingtype, the allocation of area 19 for the location of'equipment, controls o-r the like in :said. area maybe modified as desired and used for the --stora ge .of fuel and the like. Appropriate"controlling mechanisms (not shown); may. be associated-with. the body to control its direction-10f movement. :or: depth if it is so .desired. *1 have found-that, if ashort length of: the front,

portion is made movable such will-provide a iquick;response and a large 'turnin giradius. If controlmeans such as fortexample oscillatory spoiler plates are provided at or near the-rear rpen'pheryi13. such will-provide a slow resonse and -.a short :turning radius. If. control means other than the control of the;front portion. ofthe missile 'is used, it-ispreferablethatritbexof the oscillatoryitype so that no obstructions are presented to and distuicbzthe fiowfof water aroundand past the body when itistravelingtin the desired direction. 'An example oftsuitable con= 'trol'means would be a plurality of transversely :mov-able .spoiler plates or-a circular ring mountedfiush with sur- :face .12 at or near peripherylii and normally in -a;withdrawn or flush position and activated by or from. means .associated v.withthepropulsion motor. If it is .desired to .change. the normal direction of. travel :of the missileit i .would then only be necessary to cause the proper spoiler .plate to .be forcedoutintothewater and then-rwithdrawn toits: normaLposition when-the new direction or bearing hasbe n. att i ed, Ajring-typespoiler plate wouldQoper- 1ate-insubstantially:the samemannen except that itvwould be .eccentrical'l-y driven. 7

A bodyconstructedas I-haveindicatedabove produce. a -stable high-speed missile having a ;.m;inim;um of cayitation and a maximum of stability without the use of fins or the like to render it stable.

FIGURE 4 shows an improved version of my body and a method and means for reducing to a minimum the negative dynamic pressures and the disadvantages inherent in the cavity or bubble mentioned previously. The numeral 30 indicates the main or front body portion of the missile having a point or front 31, a rear edge 32 circular in shape and concentric about the longitudinal axis of the body, and a surface 33 connecting the front 31 and the rear edge 32 which increases in steepness convexly in a rearward direction with regard to the longitudinal axis, whereby a cusp is generated. The outside surface 33 of main body 30 delineates a cusp-shaped body of revolution as distinguished from a cone. The length of the main body, the degree of eusping, and the rear diameter of said body are dependent on design factors which may be determined from the formula:

tion is indicated by the numeral 34 and occupies the majority of the length of the main body. As mentioned previously, this should constitute the majority of the weight and volume of the body in order that the center of gravity will lie as far forward as is possible. The fuel storage area 35 for the venting motor 49 should preferably be located immediately to the rear of area 34. Extending inwardly and forwardly from rear surface 36 is a circular venturi wall 37 having its rearward portion convex in shape and its forward portion concave in shape, said forward portion being spaced away from wall 46 whereby the inner surface of said rearward portion and the outer surface of said wall 46 form a ring venturi or throat 56. Rigidly connected to the forward end of venturi wall 37 and extending forwardly and concentrically about the longitudinal axis of the body is a cylindrical wall 38. Connected to the forward end of cylindrical wall 38 is a transverse wall 39. Venturi wall 37, cylindrical wall 38, annular wall 39, and surface 33 form an instrumentation space 41 wherein such instruments, controls, indicating equipment or the like as may be desired may be carried in the missile. Motor section 42 is comprised of a forward venting motor portion 43 and a rearward propulsion motor portion 44. The venting motor portion 43 is perferably comprised of a plenum chamber 45 formed by walls 46, 54 and venting motor area 47 forward of chamber 45 adapted to receive a reaction type venting motor or gas producing means of the low-thrust long-burning type.

The venting motor area 47 is preferably enclosed by a cylindrical forward extension 48 of the plenum chamber wall 46, said extension 48 being adapted for rigid connection to cylindrical wall 38 whereby the motor section 42 may be rigidly and securely connected to the missile body.

My ring venturi construction is preferable for exhausting the venting gases into the bubble and, as is obvious, such a construction requires that wall 46, wall 48, and venturi wall 37 be of such construction as to provide sufiicient rigidity of motor portion 42 with regard to the main body portion 30. However, it is to be understood that departures may be made from this preferred construction with regard to exhausting the venting gases and mounting of the motor portion that will still effect substantially the same result as my venting means described herein.

Extension 48 may be connected to wall 38 in any suitable manner whereby sufficient rigidity is attained and heat transmission from area 47 to area 41 is kept to a minimum.

If desired, the inside surface of extension 48 and wall 39 may be lined with a ceramic material or the like having a high heat transfer time constant to aid in insulating the areas surrounding area 47 from the heat generated by venting motor 49 when in use.

The above is given only by way of an example and other equally efiicient means and methods will readily occur to those experienced in the art for application to the requirements of my missile.

Venting motor 49 is comprised of a combustion chamber 51 and exhaust nozzle 52. Exhaust nozzle 52 may be connected to the combustion chamber 51 in any con ventional manner and concentrically joined to the forward inside periphery of Wall 46 at point 53. Plenum chamber 45 is closed by circular wall 54, said wall being suitably adapted to receive and diffuse the exhaust gases from venting motor 49. Slots or holes 55 are preferably formed in the forward portion of the plenum chamber wall 46, the area of each slot or hole being of about the same order of magnitude as the area of the throat 56 formed by walls 37, 46. The total area of slots 55 is not considered critical, it only being necessary that said total area be sufficient that an excessive back pressure on motor 49 is not developed.

The propulsion motor portion 44 is preferably rigidly connected to motor portion 43 although it may be integral if desired. Said propulsion motor portion 44 comprises a propulsion motor area 57 similar to venting motor area 47 having located therein a combustion chamber 58,, and exhaust nozzle 59, plumbing, ignition means, and the like (not shown) necessary for operation of the propulsion motor. and a fuel storage area 61 surrounding said propulsion motor. Cylindrical wall 62 encloses area 57 and may form the inner wall of fuel storage area 61, the forward portion of said wall 62 being suitably joined to wall 54 and the rear portion being suitably joined to rear Wall 63 whereby a fluid and/or gas may be retained without danger of leakage. Area 61 must, of course, be suitably insulated from the heat generated by the propulsion motor "and the type and amount of insulation will be proportional to and dependent on the size and type of propulsion motor used. As mentioned previously, various conventional methods and means for the insulation of reaction type motors is now quite well known in the art and are readily adaptable to my missile. Rear wall 63 preferably is a flat circular wall having a diameter equal to or greater than the diameter of ring 36 for reasons that will be more fully explained later herein. The propulsion motor must be located concentrically along the longitudinal axi of the missile as is venting motor 49. As mentioned previously, the proplusion motor may be of either the conventional solid fuel or the liquid fuel type. However, the propulsion motor is distinguished from the venting motor in that it must be a high-thrust quick-burning type whereas the venting motor must be of the low-thrust low-burning type.

The precise relation between the length and diameter of a so-called cavitation bubble is complex and is fully discussed in Ofiice of Naval Research Report and Transactions Number 766, October 1947; H. Reichhardt The Laws of Cavitation Bubbles At Axially Symmetrical Bodies in a Flow.

The relation between the length and diameter of the cavitation bubble is dependent upon the cavitation coeflicient where a is the cavitation coefficient, P is the ambient static pressure, P is the pressure in the bubble, is the density of the water, and V is the velocity of the body.

For a bubble length l and a rear diameter d of wall 63, d/l should equal about 0.02 to 0.8 for a a of about 0.02 for regular travel and a a of about 0.3 for non- ,ing action. periphery of rear wall 63 should preferably just coincide should now be obvious that when a has been prescribed wand achieved b-ysufficient venting, the relationbetween :d and 1 maybe determined. By the choice o f'a proper :length'of-th-e propulsion motor portion, 8.8"Wlllb671'110l'6 fully explained later herein, thediarneter of rear Wall 63 -.may .be selected to bethes'ame as the diameter of ring r3610 facilitate launching if the, missile is to be launched .through a. tube in the conventional manner. However, since the bubble is generally convex in shape, it is not essential thatthe diameter of wall 63 be the same as that n of ring 36 and it may vary, therpreferred diameterbeing :such that the two conditions as specified hereinbelow are met. -The length of the propulsion motor portion, that -is tosaythe distance-from ring 36 to the rear surface of =wall-63 is. dependent onsubstantially two considerations.

';First,-in regular travel, a deflection of the body of an of Wall 63 is forced into the water stream, thus causing the afore mentioned restoring force. The front cone angle should, for the chosen 0' of regular travel, be about .a minimum of 3 where the length of the propulsion -imotor;-poition is. less than the bubble length. As'may now be obvious, :the length ofsaid propulsion motor portion is variable within limits and determines the moment to be expected from the afore mentioned additional restor- Second, when venting has ceased, the

with the bubble wall, thereby providing an additional stabilizing and restoring moment for the case of nonvented travel. a The fulfilling of-the above two requirements will determine the optimum length and diameter of the propulsion motor portion; that is, that it'shall be of such length that in. regular .travel a small deflection of the missile will cause a portion of" the rearperipheryof Wall 63 to touch or enter the bubble wall, and when substantially no vent- -ing is present, the periphery of wall 63 will be in substantially continuous contact'with the wall of .thenow changedbubble,

-Therelation of the bubble wall during regular travel with:regard to the rear portion of the missileis shown in FIGURE 5. 1 As shown therein, the bubble begins at about edge 32 and extends rearwardly, the 'bubble wall being substantially circular convex in shape and completely-enclosing butinot touching propulsionmotor portion 44. The distance thatYthe-bubble extendspast Wall .63 .will. substantially depend onthe velocity of the missile.

vThe relation-of the forward portion of the bubble Wall during non-vented travel, i.e., afterthe propulsion and venting motors have ceased operation, isshown in FIG- URE 6. When propulsionand ventinghas ceased, the

"causes the missile-to move forward through the water 'eat preferahlyraxhi-gh mate of speed. .-As previously Texplained, a cavity is formed ibehind the-missil e,-beginning rsubstantially at 1 edge 32 -.-and: extending rearwardly pastreariwall 63 ofthe;propulsion motonportiona Due 'ltO the cusp .shape of th'ewmain body-=30, :the forward .portion oftthe wallrofthe cavitygexten'ds entirely around eandpast: the a rear: motor portion 44, said forward; portion being-substantially circularconvex iniform. Thediami-eter of .rearww-all163 beingpreferably of -.such diameter :that .the :peripher-y thereof .is;-. immediately adjacent to the surface;of;.cavity wall 65, the exhaust gases .of the venting-motorcompletely fill: the spacebetween the cavity wa-ll. 65 and thegperiphery of ;..propulsion .motor, portion -44. .The gases generatedin combustion chamber 51 .of -venti-ng'motor-49; are exhausted into chamber-45 through cexhaust nozzle:52. Said igases-expand and impinge on :the rear :Wall *54 'of chamber 45, thus reducing their velocity and completely:fillingsaid-chamber -45. 'As the pressure in said chamber builds up, the gases in turn are forcedkout through *zSlQtS or 1 ports 55 and .further expand into cavity 64. Due to the location and. angle "cave section of the cavity-64 and are directed in a -forwardly direction, "thus filling :said cavity and further *reducing their velocity. When-cavity "64 -becomes filled, the exhaust gases-areimturn forced out through throat '56" of'the ring venturi. 'It' is to be "noted that for j this -embodiment the' final ex-it velocity of 1 the exhaust: gases of the ventingmotor is 'below-theinitial'velocityof said j gases and -do 'not'materially' aid in-the propulsion of the missile. It'may be-furthernotedthat if the-initial -velocity of the gases through exhaust nozzle '52 may-be 'exhausted at asufiiciently' low velocity, cavity 64 may be eliminated and slots 55 or thelike relocated such that the gases passing therethrough will be directed -'directly into throat56. The'venting motorshoul'd prefiera-bly continue to operate -after the thrust motor has "stoppedin order to keep theremaining cavity;filledto substantially static pressure 'and negate -the undesirable "effects of an'unfilled cavity. :As the exhaust gases-of the venting motor leave the ring -venturi, -they further 'expand and completely *fil-lthe space "between the wall of cavity 65 and the periphery of v propulsion motor: por- -tion- 44. As longas the-pressureexerted'on the surface "of the water 'form-ing the cavityis at least static pressure, substantially no undesirable effects-{much as for example, negative dynamic pressures, willebe created by thecavity. -As=said gases pass over the peripheryof said "rearwail '63,theycombi-newith the exhaust gases-of j the thrust motorto- 'fill the -balanceof the cavity.

Since thefront '31issubstantially a'point, little or no cavitation occurs there as the body *passes throulgh the water. Further due to'the 'c'usp-shaped'smoo'thsurface 33 a positive pressure is always ;present-- on said surface 55 and substantially no cavitation :occurs along the entire "lengthof the -rnain5'body30 as it moves through the water. Still further, no cavitation-is present on the'profpulsion =motor portion 44 during regular travel due to *thefact'that it is entirely'containedwithin the bubble or-cavity and little or no cavitation isapresent thereon during non-vented travel due to the fact that all'but'a smalkportionis contained "within'the now charge'dbubble kor'cavi-ty. "It may'now lbfi'ObVlOllS that little'or no cavi- ".tation occurs on the missile to 'disturb'itsstabilitychar- 'acteristics, andfthe missile remainsrstable, said "stability being in'dependentof velocityzan'd .the'velocity Zbeing subf stantiallyLlimitedjonly by the thrust "that: the propulsion obvious that even for the case of a simple straightrunning missile. as herein described, said missile'provides substantial practical and tactical advantages over presentdaytorpedoes, i.e., it can be fired from substantialdis- 5 tances and, due to its stability and high speeds, -reach its target before being detected or substantial evasive action can be taken to avoid it.

Still further, I have found that with certain modifications a missile incorporating the present invention is highly useful as a missile designed to be fired out of the earths atmosphere and to re-enter the atmosphere at some remote point. Conventional missiles having fixed control surfaces are not entirely satisfactory in that said surfaces are burned oif, seriously damaged, or incapacitated due to the heat generated therein during re-entry into the atmosphere. Since my missile requires no such stabilizing surfaces this problem is completely eliminated, the missile remaining stable at substantially all times during supersonic travel.

For purposes of re-entry into the earths atmosphere, if the front surface of the main body is modified to be or become a relatively flat or blunt circular disc, such as for example by making the extreme front portion removable or by forming it of a material or materials that will be burned away by friction only until a relatively flat front surface having the necessary diameter is secured, the resulting front surface will cause the initial shock wave to be shifted away from the body. Under these circumstances substantial heating will occur only at the periphery of the flat or blunt front surface; hence, only the periphery of the front surface need be cooled or made of a ceramic material or the like sufficient to withstand the heat generated at this point. Due to the cusp shape of the main body portion and the resulting positive pressures on the body additional substantial heating will occur only at the rear edge or periphery of the main body portion. The detrimental effects of heating at this point may be alleviated by forming said rear periphery of a suitable ceramic material similar to or the same as that used at the front periphery of the missile and modifying the venting motor and the means for exhausting the exhaust gases of the venting motor whereby the exhaust gases will be exhausted at a velocity suflicient to shift the trailing or second shock wave away from the rear periphery of the main body portion. If the exhaust is a coolant, additional benefits may be derived.

This invention is not limited to the particular details of construction, materials, and processes described, as many equivalents will suggest themselves to those skilled in the art. It is accordingly desired that the appended claims be given a broad interpretation commensurate with the scope of the invention within the art.

What I claim is:

1. In an elongated missile-the combination comprising: a front surface that is substantially a point; a rear surface having an opening therein concentric about the longitudinal axis of the missile, said rear surface having a diameter greater than said front surface and concentric therewith; a surface connecting said front surface and said rear surface, said connecting surface having a continuous ceratoid cusp shape and a length considerably greater than its largest diameter; a reaction motor, said motor being mounted forwardly of said opening and concentric about the longitudinal axis of said missile and adapted to propel said missile in a forwardly direction; a first closed compartment surrounding and separated from said reaction motor; and a second compartment comprising the majority of the forward length of the missile having located therein the majority of the weight of said missile whereby the center of gravity of said missile is located in a forwardly direction, the cusping of said connecting surface being such that the center of pressure of said missile lies rearwardly of said center of gravity.

2. The combination as defined in claim 1 wherein the reaction motor is of the liquid fuel type and a fuel storage compartment is provided between said first and second compartments.

3. In a missile the combination comprising: a main body portion, said main body portion being comprised of 10 a front portion, an annular rear surface having a diameter greater than said front portion and concentric therewith, a surface connecting said front portion and said rear surface, said connecting surface having in general a cusp shape and a length greater than its largest diameter, a first compartment comprising the majority of the length of said main body portion having located therein a substantial portion of the weight of said missile, a first reaction motor mounted rearwardly of said first compartment and concentric about the longitudinal axis of the missile, and a second compartment surrounding and separated from said first reaction motor; a rear motor portion; means rigidly connecting said rear motor portion and said main body portion and adapted to receive and exhaust the gases of said first reaction motor around and past said rear motor portion; and a second reaction motor, said second reaction motor being mounted in said rear motor portion concentric about the longitudinal axis of said missile and adapted to propel said missile in a forwardly direction.

4. In a missile the combination comprising: a main body portion, said main body portion being comprised of a front portion, an annular rear edge having a diameter greater than said front portion and concentric therewith, a surface connecting said front portion andsaid rear edge, said connecting surface having in general a ceratoid cusp shape and a length considerably greater than its largest diameter, a first compartment comprising the majority of the length of said main body portion having located therein a majority of the weight of said missile, a first reaction motor mounted rearwardly of said first compartment and concentric about the longitudinal axis of the missile, and a second compartment surrounding and separated from said first reaction motor; a rear motor portion; means rigidly connecting said rear motor portion and main body portion and adapted to receive and exhaust the gases of said first reaction motor around and past said rear motor portion; and a second reaction motor, said second motor being mounted in said rear motor portion concentric about the longitudinal axis of said missile and adapted to propel said missile in a forwardly direction, the cusping of said connecting surface being such that the center of pressure of saidmissile lies rearwardly of the center of gravity of said missile.

5. In a missile the combination comprising: a main body portion, said main body portion being comprised of a front portion, an annular rear edge having a diameter greater than said front portion and concentric therewith, a surface connecting said front portion and said rear edge, said connecting surface having in general a ceratoid cusp shape and a length considerably greater than its largest diameter, a first compartment comprising the majority of the length of said main body portion having located therein a substantial portion of the weight of said missile, whereby the center of gravity of said missile lies forwardly of the otherwise normal location of the center of gravity, a first reaction motor mounted rearwardly of said first compartment and concentric about the longitudinal axis of the missile, and a second compartment surrounding and separated from said first reaction motor; a rear motor portion, said rear motor portion having a forward taper; means rigidly connecting said rear motor portion and said main body portion and adapted to receive and exhaust the gases of said first reaction motor around and past said rear motor portion; and a second reaction motor, said second motor being mounted in said rear motor portion concentric about the longitudinal axis of said missile and adapted to propel said missile in a forwardly direction, the cusping of said connecting surface being such that the center of pressure of said missile lies rearwardly of the center of gravity of said missile.

6. In a missile the combination comprising: a main body portion, said main body portion being comprised of a front portion, an annular rear edge having a diameter greater than said front portion and concentric therewith,

:1'1 a surface .connectingsaid front, portion-randisaid rear edge, saidconnecting surface zhavingtimgeneraliatceratoid cusp -sh ape.tand,a lengthconsiderablytgreaterathan, its largest diameter, a first.compa-rtment comprising the majority of the-length of said main bodylportion having located therein asubstantial portion of the weight of saidrnissile whereby .the .centerof ,gravity of said .missile.liesforwardly of a the otherwise normal location of the center ofgravity, a i first reaction motormmounted rearwardly of said first comvpartmentandconcent-ric aboutthe longitudinal axis of the missile, and a second compartment surrounding and .separatedtfromtsaid first reaction motor; a rear motor ,portionhavingasecond frontportion and a rear portion, .saidrear portionbeing larger than said second front portion; a.second reaction motor,-saidtsecond motor being mounted in.said.rear motor portion concentric about the longitudinal .axis of said missile andtad-apted to propel said missile in. aforwardly direction; and means rigidly connecting said rear motorqportion and said main .body portion and adapted to receive and exhaust the gases of said first reaction. motor aroundandpastrsaid rear motor portion, the cusping of said connectingsurface being such ithatthe centerof pressure of saidmissile lies rearwardly .of the center .ofgravity of said. missile. v

7. .In a missile adapted for travel in water the combina- -tiontcomprisingz adorward body .o'frevolutionhaving in general .a cusp shape,-said.body having a front surface that is-ssubstantiallya point, an annular rear surf-ace havjinga diameter greater than said front surface and 'concentric therewith, a first compartment comprising the,

majority .of thelengthof said .bodyl-havinglocated therein asubstantialportion of the weight of said missile, a first reaction motor mounted rearwardly of said first compart- .ment..and concentric aboutthe longitudinal axis of the ,missile, anda secondeompartmentsurrounding and separated'from said first reaction motor; a rear motor portion, said rear motor portion having a rearward diameter greater than. its. forward diameter; means rigidly connecting said rear motor portionand: said main body portion andadapted to receive an exhaust the gases of said first reactiontmotoraroundrand pastsaidrearsmotor portion; and asecond reaction ,motor, said second motor being mounted in Vsaidrear motor portion concentric about the longitudinal axis of s'aidmissile andadapted to propel said missile in afforwardly direction.

8. In a missile,adaptedforltravel in water the combination comprising: a forward relatively slender body of revolution having in general a cuspshape, saidbody-having a' front surface that is substantially a point,. an annular rear surface havingtadiameter greater than said front surface and concentric therewith, a surface connectingsaid front surface and-said rear surface havinga length greater than its greatest diameter, a first compartment-comprising the majority of the lengthrof said bodyhaving located therein a substantial portionofrthe weightiof saidrmissile,

a first low-thrust reaction motor mounted rearwardlyof said first compartment and concentriclabout the longitudinal axis of the/missile, and a second compartmentsnrrounding and separated from said, first reaction, motor; a

rear motor portiontdisposed rearwardly of said annular rear surfiacethaving a front portion-fland a rear, portion, said rear portion having. a diameter. such thata small-deflection of the missile during regular travelewill cause said rear portion to touch the walltofithe bubble-created by the motion of the missile, andduring non=ventedtravel .be

,of thetweight ofsaid missile, .a first low-thrust reaction .motor, mounted rrearwardly ,ofsaid first compartmentand concentric about the longitudinal axisof vthe missile, a

-12 in,contact-Mithdhehubble .wallpasecond thigh-thrust .re-

action motor, said second motor'lbingmounted' in said rearvmotor,portiomconcentrictabout.rthe longitudinal axis of Ysaidmissile and adapted to propel .saidmissile in a forwardly direction; and means rigidly connecting said-rear 7 -motor portion and said forward body. adapted to receive and exhaust the gases of said first reaction motor around and past said rearmotor portion, .thevcusping of said body .being sucht'hat thecenterrof pressure of said'body lies rearwardly of the centerof gravity oftsaid body.

'9. .In a missileadapted for travel in water the combinationcompris'ing: a forward relativelyslender body of revolution having in general a cusp shape, said body having a front surface that is substantially a point, .an annular rear edge having a diameter greater than 's-aid front surface and concentric therewith, a surface connecte ing said front surfaceand said rear surface having a lengthconsiderablygreater-than its greatest. diameter, a \firstcompartment comprising thetmajority of the length ofsaid body having located therein .a substantial portion .secondcompartmentsurrounding and separated from said 'firstreactionmotor, said second compartment having a rear wall extendinginwardly an d'forwardly and forming .theout'side surface of a ring venturi; arear motor portion disposedirearwardly-df said annular rear edge having a ,front portion and a rear portion, said rear portion having a diameter such that a small deflection of the missile during regular travel will cause said rear portion to touch the wall of thetbubble created by the motion oftthe missile .and' duringnon-vented travel be in contact with the bubble wall; a secondfhigh thiust' reaction motor, said second motor being mounted in said rear pontion concentric about the longitudinalaxis of said missile and adapted topropel said missile in aforward-ly direction; and meansrigidly connecting saidrear motor portion and said forward body adapted to receive and; exhaust the gases of said first 4O "reaction motor around ,and pastsaid rear motor portion comprising'a plenum chamber adapted to receive the exhaust gasesof 'saidfirst reaction motor and disposed inwardlyfrom said second chamber-rear wall and adapted 'tofform'the inside'surface 'of a ring venturi, said'plenum chamber having'ajplurality of openings whereby said gases may beexhausted'through said ring venturi,'the cusping-of said'-'body"being" such" that ,thecenter'of pressure 10. The combination as defined in claim 9"whereintsaid second 'co'mpartment is adapted to contain-means for con-' *trolling -the--missile-and additionally including a' third com- 'partment surroundingfind separated from said second reactionmotor.

.fReic'erences Citedin the file of this patent UNITED "STATES PATENTS 

